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National Pollutant Discharge Elimination System (NPDES)

Combined Sewer Overflows in the Great Lakes Basin

There are 151 NPDES permits which authorize discharges from CSOs to the Great Lakes Basin. Select the tabs below for the list of CSO permittees in the Great Lakes Basin in each state.

Map of CSO communities that drain to the Great Lakes Basin

Public Notification Requirements for the Great Lakes

Public Notification Requirements for Combined Sewer Overflows to the Great Lakes Basin - On January 8, 2018, EPA published the final Public Notification Requirements for Combined Sewer Overflows to the Great Lakes.

Reports to Congress

Report to Congress: Combined Sewer Overflows into the Great Lakes Basin (2016) - This report presents EPA’s assessment of the implementation status of long-term CSO control plans (LTCPs) in the Great Lakes Basin. The report includes a summary of existing information on the occurrence and volume of discharges from CSOs in the Great Lakes Basin during 2014.

Report to Congress: Combined Sewer Overflows to the Lake Michigan Basin (2007) - This report assesses the occurrence of CSOs in the Lake Michigan drainage basin. The report identifies EPA actions to ensure that state permitting and enforcement efforts are consistent with the national CSO control policy and Clean Water Act, and lead to further reduction in CSO discharges to Lake Michigan.

Great Lakes National Program Office

The Great Lakes National Program Office (GLNPO) coordinates U.S. efforts with Canada under the Great Lakes Water Quality Agreement (GLWQA) to restore and maintain the chemical, physical, and biological integrity of the Great Lakes Basin Ecosystem, which includes Lakes Superior, Michigan, Huron, Erie, and Ontario.

Illinois

There are 42 NPDES permits for CSO discharges in the Great Lakes Basin in Illinois. All 42 of these NPDES CSO permits are in the Chicago metropolitan area and are part of the Tunnel and Reservoir Plan (TARP). The Metropolitan Water Reclamation District of Greater Chicago provides information on CSO discharges from the TARP system and has developed a program where reaches of the Chicagoland waterway map Exit will be color coded based on CSO data compiled by staff. The geographical boundaries of the segments are listed in the District's CSO Notification Plan Exit.

Map of CSO communities in Illinois that drain to the Great Lakes BasinThe following Illinois permits are in the Great Lakes Basin:

Municipal Operator of CSO NPDES Permit Number Water Body Directly Discharged Into
Brookfield CSO - TARP ILM580032 Salt Creek
Chicago CSO - TARP IL0045012 Chicago CSO -  North Shore Channel, North Branch Chicago River, Little Calumet River, Calumet River, Chicago River, South Branch of Chicago River (SBCR), South Fork of SBCR, Chicago Sanitary and Ship Canal, Collateral Channel and Des Plaines River
City of Blue Island CSO - TARP ILM580031 Cal-Sag Channel
City of Calumet City CSO - TARP ILM580025 Little Calumet River
City of Evanston CSO - TARP ILM580002 North Shore Channel
City of Harvey - TARP ILM580020 Little Calumet River
Des Plaines - TARP ILM580026 Des Plaines River
Dixmoor CSO - TARP ILM580011 Little Calumet River
Franklin Park CSO - TARP ILM580029 Des Plaines River
Golf CSO - TARP IL0072389 North Branch Chicago River
LaGrange Park CSO - TARP ILM580008 Salt Creek
Lansing CSO - TARP ILM580027 Little Calumet River
Lincolnwood CSO - TARP ILM580034 North Shore Channel
MWRDGC  IL0028061,
IL0047741, IL0028053, IL0028088
Little Calumet River, Weller's Creek, Chicago Sanitary and Ship Canal, North Shore Channel
Park Ridge CSO - TARP ILM580014 Des Plaines River
Phoenix CSO - TARP IL0072834 Little Calumet River
Posen CSO - TARP ILM580037 Cal-Sag Channel
Riverside CSO - TARP ILM580015 Des Plaines River
Skokie CSO - TARP ILM580036 North Shore Channel
Summit CSO - TARP ILM580033 Chicago Sanitary and Ship Canal
Village of Arlington Heights CSO - TARP ILM580006 Weller's Creek
Village of Burnham CSO - TARP ILM580018 Grand Calumet River
Village of Calumet Park CSO - TARP ILM580016 Cal-Sag Channel
Village of Dolton CSO - TARP IL0052426 Little Calumet River
Village of Forest Park CSO - TARP ILM580019 Des Plaines River
Village of LaGrange CSO - TARP ILM580009 Salt Creek
Village of Lyons CSO - TARP ILM580004 Des Plaines River
Village of Maywood CSO - TARP ILM580022 Des Plaines River
Village of Melrose Park CSO - TARP ILM580003 Des Plaines River
Village of Morton Grove CSO - TARP ILM580005 North Branch Chicago River
Village of Niles CSO - TARP ILM580035 North Branch Chicago River
Village of North Riverside - TARP ILM580030 Des Plaines River
Village of River Forest CSO - TARP ILM580024 Des Plaines River
Village of River Grove CSO - TARP ILM580021 Des Plaines River
Village of Riverdale CSO - TARP ILM580007 Little Calumet River
Village of Schiller CSO - TARP ILM580013 Des Plaines River
Village of South Holland CSO - TARP ILM580010 Little Calumet River
Village of Stickney CSO - TARP ILM580023 Chicago Sanitary and Ship Canal
Village of Wilmette CSO - TARP ILM580012 North Shore Channel

EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilites.

Indiana

There are 17 NPDES permits for CSO discharges in the Great Lakes Basin in Indiana.

Map of CSO communities in Indiana that drain to the Great Lakes Basin

Municipal Operator of CSO NPDES Permit Number Great Lake Discharged To Water Body Directly Discharged Into
Auburn IN0020672 Lake Erie Cedar Creek
Berne IN0021369 Lake Erie Habegger Ditch, Spruger Ditch
Butler IN0022462 Lake Erie Big Run
Chesterton IN0022578 Lake Michigan East Arm Little Calument River
Crown Point IN0025763 Lake Michigan Main Beaver Dam Ditch
East Chicago IN0022829 Lake Michigan Indiana Harbor Canal, Grand Calument River
Elkhart IN0025674 Lake Michigan Elkhart River, St. Joseph River, Christina Creek
Fort Wayne IN0032191 Lake Erie Maumee River, St. Mary's River, Spy Run Creek, St. Joseph River, UNT
Gary IN0022977 Lake Michigan Grand Calumet River, Little Calumet River
Hammond IN0023060 Lake Michigan Grand Calumet River, East Arm Little Calumet River
Michigan City IN0023752 Lake Michigan Trail Creek
Mishawaka IN0025640 Lake Michigan St. Joseph River, Eller Ditch
Nappanee IN0021466 Lake Michigan Berlin Court Ditch, Armey Ditch
South Bend IN0024520 Lake Michigan St. Joseph River
Valparaiso IN0024660 Lake Michigan Salt Creek
Wakarusa IN0024775 Lake Michigan Werntz Ditch
Waterloo IN0020711 Lake Erie Cedar Creek

EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilites.

Michigan

There are 33 NPDES permits for CSO discharges in the Great Lakes Basin in Michigan.

Map of CSOs in Michigan that drain to the Great Lakes Basin

Municipal Operator of CSO NPDES Permit Number Great Lake Discharged To Water Body Directly Discharged Into
Bay City WWTP MI0022284 Lake Huron Saginaw River
Birmingham MI0025534 Lake Erie Rouge River
Bloomfield Village CSO MI0048046 Lake Erie Rouge River
Chapaton RTB MI10025585 Lake Erie Chapaton Canal
Dearborn CSO MI0025542 Lake Erie Rouge River; Detroit River
Detroit WWTP MI0022802 Lake Erie Rouge River; Detroit River
East Lansing WWTP MI0022853 Lake Michigan Red Cedar River
Essexville WWTP MI0022918 Lake Huron Saginaw River
George W. Kuhn Drainage District CSO RTB MI0026115 Lake Erie Red Run Drain
Inkster/Dearborn Heights CSO MI0051837 Lake Erie Lower Rouge River
Iron Mountain Kingsford WWTP MI0023205 Lake Michigan Menominee River
Lansing WWTP MI0023400 Lake Michigan Grand River; Red Cedar River
Manistee WWTP MI0020362 Lake Michigan Manistee Lake
Manistique WWTP MI0023515 Lake Michigan Manistique River
Milk River CSO RTB MI0025500 Lake Erie Milk River
Mt. Clemens WWTP MI0023647 Lake Erie Clinton River
Niles WWTP MI0023701 Lake Michigan St. Joseph River
North Houghton Co W&SA CSO MI0043982 Lake Superior St. Louis Creek; Douglas Creek
Norway WWTP MI0020214 Lake Michigan White Creek
Oakland County - Acacia Park CSO RTB MI0037427 Lake Erie Rouge River
Port Huron WWTP MI0023833 Lake Erie St. Clair River; Black River
Redford TWP CSO MI0051829 Lake Erie Ashcroft-Sherwood Drain
River Rouge CSO MI0028819 Lake Erie Rouge River
Saginaw TWP WWTP MI0023973 Lake Huron Tittabawassee River
Saginaw WWTP MI0025577 Lake Huron Saginaw River
Sault St. Marie WWTP MI0024058 Lake Huron St. Marys River; Edison Power Canal
South Macomb SD Martin RTB MI0025453 Lake Erie Lake St. Clair
Southgate/Wyandotte CSO RTF MI0036072 Lake Erie Trenton Channel
St. Joseph CSO MI0026735 Lake Michigan St. Joseph River
Wayne County/ Dearborn Heights CSO MI0051489 Lake Erie Middle Rouge; Upper Rouge River; Lower Rouge River
Wayne County/ Inkster CSO MI0051471 Lake Erie Lower Rouge River
Wayne County/ Inkster/ 
Dearborn Heights CSO
MI0051462 Lake Erie Lower Rouge River
Wayne County/ Redford/ 
Livonia CSO
MI0051535 Lake Erie Ashcroft-Sherwood Drain; Upper Rouge River; Bell Branch of Upper Rouge River

The Michigan Department of Environmental Quality prepares annual reports Exit summarizing CSO, sanitary sewer overflow and retention basin discharge information. 

Appendix A of the Report to Congress: Combined Sewer Overflows into the Great Lakes Basin has information on CSOs in communities in the Great Lakes Basin during 2014.

EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilites.

New York

There are 17 NPDES permits for CSO discharges in the Great Lakes Basin in New York. 

Map of CSOs in New York that drain to the Great Lakes Basin

Municipal Operator of CSO NPDES Permit Number Great Lake Discharged To Water Body Directly Discharged Into
Auburn STP NY0021903 Lake Ontario Owasco Outlet
Boonville WWTP NY0020494 Lake Ontario Mill Creek
Buffalo Sewer Authority NY0028410 Lake Erie Niagra River, Buffalo River, Scajaquada Creek, Black Rock Canal, and Cazenovia Creek
Canastota WPCF NY0029807 Lake Ontario Canastota Creek
City of Oswego NY0029106,
NY0029114
Lake Ontario Oswego River
Dunkirk WWTP NY0027961 Lake Erie N/A
Frank E. VanLare STP (Rochester) NY0028339 Lake Ontario Genesee River and Irondequoit Bay
Gouverneur STP NY0020117 St. Lawrence Oswegatchie River
Lockport WWTP NY0027057 Lake Ontario Barge Canal and Eighteen mile Creek
Massena WWTP NY0031194 St. Lawrence Grasse and Raquette Rivers
Medina WWTP NY0021873 Lake Ontario Barge Canal and Oak Orchard Creek
Niagra Falls WWTP NY0026336 Lake Erie Niagra River
North Tonawanda WWTP NY0026280 Lake Ontario Niagara River
Ogdensburg WWTP NY0029831 St. Lawrence St. Lawrence River
Syracuse Metro WWTP NY0027081 Lake Ontario Harbor Brook
Watertown WPCP NY0025984 Lake Ontario Black River

EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilites.

Ohio

There are 43 NPDES permits for CSO discharges in the Great Lakes Basin in Ohio.

Map of CSO communities in Ohio that drain to the Great Lakes Basin

Municipal Operator of CSO NPDES Permit Number Great Lake Discharged To Water Body Directly Discharged Into
Akron OH0023833 Lake Erie Cuyahoga River
Avon Lake OH0023981 Lake Erie N/A
Bowling Green OH0024139 Lake Erie Poe Ditch
Bucyrus OH0052922 Lake Erie Sandusky River
City of Fostoria OH0052744 Lake Erie E Br Portage River
Clyde OH0024868 Lake Erie Raccoon Creek
Columbus Grove OH0024759 Lake Erie Plum Creek
Defiance OH0024889 Lake Erie Maumee River
Delphos OH0024929 Lake Erie Jennings Creek
Delta OH0020974 Lake Erie Bad Creek
Deshler OH0022471 Lake Erie Brush Creek
Elyria OH0025003 Lake Erie Black River
Euclid OH0031062 Lake Erie N/A
Fayette OH0025127 Lake Erie Unnamed tributary to Deer Creek
Findlay OH0025135 Lake Erie Blanchard River
Forest OH0025151 Lake Erie Forest Simpson Ditch to Blanchard River
Fremont OH0025291 Lake Erie Sandusky River
Gibsonburg OH0029122 Lake Erie Hurlbut & SR 300 Ditch (to Portage River)
Greenwich OH0020486 Lake Erie SW Branch of Vermillion River
Hicksville OH0025771 Lake Erie Mill Creek
Lakewood OH0026018 Lake Erie N/A
Lima OH0026069 Lake Erie Ottawa River
Monroeville OH0020095 Lake Erie West Branch Huron River
Montpelier OH0021831 Lake Erie St. Joseph River
Napoleon OH0020893 Lake Erie Maumee River
NEOSRD OH0043991 Lake Erie N/A
North Baltimore OH0020117 Lake Erie Rocky Ford Creek
Norwalk OH0052604 Lake Erie Rattlesnake Creek
Oak Harbor OH0026841 Lake Erie Portage River
Paulding OH0020338 Lake Erie Flat Rock Creek
Payne OH0021326 Lake Erie Flat Rock Creek
Perrysburg OH0021008 Lake Erie Maumee River
Port Clinton OH0052876 Lake Erie Portage River
Sandusky OH0027332 Lake Erie Sandusky Bay
Swanton OH0020524 Lake Erie Al Creek
Tiffin OH0052949 Lake Erie Sandusky River
Toledo OH0027740 Lake Erie Maumee River
Upper Sandusky OH0020001 Lake Erie Sandusky River
VanWert OH0027910 Lake Erie Town Creek
Wapakoneta OH0027952 Lake Erie Auglaize River
Wauseon OH0023400 Lake Erie North Turkeyfoot Creek
Willard OH0028118 Lake Erie Jacobs Creek
Woodville OH0020591 Lake Erie Portage River

View the Ohio Environmental Protection Agency's online interactive map Exit of CSO outfall locations and permit information. 

The Ohio Environmental Protection Agency's website Exit has more information about the Ohio CSO Control Program.

EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilites.

Pennsylvania

There is one NPDES permit for CSO discharges in the Great Lakes Basin in Pennsylvania.

Map of CSO communities in Pennsylvania that drain to the Great Lakes Basin

Municipal Operator of CSO NPDES Permit Number Great Lake Discharged To Water Body Directly Discharged Into
City of Erie PA0026301 Lake Erie Lake Erie

EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilites.

Wisconsin

There are two NPDES permits for CSO discharges in the Great Lakes Basin in Wisconsin.

Map of CSO communities in Wisconsin that drain to the Great Lakes Basin

Municipal Operator of CSO NPDES Permit Number Great Lake Discharged To Water Body Directly Discharged Into
Milwaukee WI0036820 Lake Michigan Lake Michigan
Superior WI0025593 Lake Superior Lake Superior

EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilites.